How do I design a gun?

Hello there, I would like to design a new gun, but I don’t know how. Can anyone help me? Thanks.

You will get better help for such topics in the forums.

https://forums.unrealengine.com/forumdisplay.php?5-Content-Creation

You probably want to google the same question.
“How to model a gun”

like this: LMGTFY - Let Me Google That For You